This invention relates to the treatment of tree stumps and more particularly the application of a liquid treatment material flowed onto a tree stump through a guide bar simultaneous with the falling of a tree.
It has been discovered that the severed surface of a stump resulting from tree falling is susceptible to growing undesired fungus that can and does detrimentally affect surrounding vegetation. In some jurisdictions, treatment of the severed surface is mandated to prevent such growth. Whereas a form of treatment is to equip a worker with a spray bottle who follows the tree harvester and manually sprays the treatment material onto the tree stump, it is more acceptable to incorporate the treatment process in the tree cutting procedure. Thus, a guide bar is provided with a feed channel along its length and the liquid material is directed from a reservoir of the liquid material (provided, e.g., on the tree harvester) into the channel. Small dispersal holes on the bottom side of the guide bar and in communication with the feed channel releases the liquid treatment onto the stump surface but without applying material onto the severed end of the log that is cut from the tree stump, it being undesirable to apply the treatment onto the wood that is to be sawn into lumber.
Guide bars have long been produced with feed channels for dispensing lubricant into the guide grooves for lubricating the chain. Certain of this technology is applied to the dispersement of the liquid stump treatment. The bar is provided with an inlet hole that is aligned with a conduit that extends from a reservoir provided on the tree harvester. The inlet hole directs the liquid treatment into the feed channel and onto the stump through appropriate dispersal holes. The solution as described does not totally take care of the dispersement requirement as the bars are made to be reverse mounted, i.e., so that the leading edge becomes the trailing edge and vice versa whereby the top and bottom sides are reversed. Thus, such a bar is provided with two independent sets of dispersal holes (top and bottom) and a second feed channel and top and bottom inlet holes.
The solution is still not complete because different tree harvesters will have reservoir conduits directed to a top or a bottom inlet hole as mounted on the tree harvester. It is not feasible to provide different bars for different harvesters. This means that inlet holes have to be provided for both sides of the bar for both sets of dispersal holes. Complicating the task further is that the locations of the reservoir conduits may require different locations of the inlet hole along the bar length (whether top or bottom) so that several inlet holes at different locations on both sides need to be provided if a standard bar is to fit the numerous different tree harvesters.
The inlet holes into the particular feed channel to be used for treatment dispersal must either be connected to the reservoir conduit or must be plugged. An unplugged inlet hole will result in leaking of the treatment material onto the equipment and the surrounding area which is not acceptable.
Plugging undesired inlet holes is a problem for operators. Not only does the operator have to figure out which holes have to be plugged, it is also important that the plugs are properly installed, i.e., to properly seal the hole and to avoid any portion of the plug from penetrating above the bar surface. Such plugs have to be fit entirely in the inlet hole and are difficult to handle. It is accordingly an object of the present invention to provide an improved inlet hole plugging system that facilitates the task of plugging the unused inlet holes of a guide bar.
Ideally the bar is a laminate bar which consists of a center laminate fused between two outer laminates. The feed channels are formed in the center laminate and matching inlet holes are provided in the outer laminates. When assembled together, the inlet holes are aligned with each other and with a channel portion that receives and transmits the liquid treatment. The receiving channel portion is enlarged over that of the inlet holes and the remainder of the channel. A disk placed in the enlarged channel portion prior to assembly is thereby trapped between the two inlet holes, i.e., it is oversized relative to the inlet holes and to the remaining channel so that it will stay within the enlarged channel portion. However, it has a thickness less than the thickness of the center laminate and can move from one side laminate to the other.
A reservoir conduit connected to the inlet hole at either side produces liquid flow into that inlet hole to force the disk against the opposite inlet opening to seal off that hole or opening. Thus, regardless of whether the reservoir inlet connects to the top or bottom of the bar, liquid will enter the channel and not exit the opposed inlet hole.
The above describes a first embodiment of the invention which accommodates a guide bar adapted to fit a standardized tree harvester that directs liquid treatment into the top side of the bar plus a standardized tree harvester that directs liquid treatment into the bottom side of the bar but at the same location lengthways of the bar. Whereas a substantial percentage of tree harvester use is thereby accommodated, those tree harvesters that are not standardized and provide conduit connection at different locations, top and bottom, are not accommodated by this solution.
A second embodiment provides for a guide bar having a number of inlet holes to accommodate a wider range of tree harvesters. Opposing pairs of inlet holes are provided at the different locations as dictated by the different harvesters. A pair of disks that are spring biased apart are provided in each channel portion to close off all inlet openings. Whichever hole is connected to a reservoir conduit, the pressure of the inflow of treatment material forces retraction of that disk and the internal pressure of the liquid treatment material enhances the urging of the other disks against the respective inlet openings to prevent leakage of the material.
A still further embodiment provides each inlet hole with laterally directed narrow passages or grooves between the laminates, in some cases leading from the inlet hole to the guide slots of the edge and in other cases leading from the inlet holes to the mounting slot. Manually insertable strips are pressed into these narrow passages or grooves and over the holes to close off the holes not in use. Because the narrow passage also leading to the to-be-used inlet hole also needs to be closed, a blocking strip is inserted into that passage but not across the hole.
Whereas the invention is preferably applied to laminate bars, a solid bar may also be equipped with the inlet holes and channels as required for the invention. For example, tubes can be embedded in the solid bars to form channels and inlet openings.
These and other variations of the invention will be more readily understood and appreciated upon reference to the following detailed description and accompanying drawings referred to therein.